Unholy Legacy by Misty Dietz

Acerbic exorcist Katherine Evangelista keeps her tongue razor sharp and her elegant night club the nerve center of her demon hunting activities. Her business runs on logic and her relationships on sarcasm because experience has taught her emotions are dangerous. Even if she hasn’t been happy, she’s been in control…until her ex and a daughter of Lucifer show up and make her life Hell.

Swashbuckling Ari Grimmson is an ancient Viking warrior with a big laugh, a big ego, and an even bigger plan. He’s returned after a three-year absence to vanquish the Demon Princess and win back Kat’s prickly heart. But his plan falls apart when Kat begins to empathize with Leviathan, the perplexingly philosophical Demon Princess, who claims she’s nothing like her notoriously evil father…a declaration Kat relates to on a deeply personal level.

As Leviathan’s demon horde begins to surge through the island and Katherine’s health begins to fail, she doesn’t know whom to trust. The man who knows her best, but broke her heart…or the Demon Princess who promises to heal her suffering once and for all. If Kat chooses wrong, it’s more than her own fate that hangs in the balance…she could leave an unholy legacy for the entire human race.